[INFO] cloning repository https://github.com/philipahlberg/lookahead
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/philipahlberg/lookahead" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fphilipahlberg%2Flookahead", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fphilipahlberg%2Flookahead'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 6c0ca3c5ccf3ff1d5a34fd12fb3211689d689d22
[INFO] checking philipahlberg/lookahead against master#b7ebc6b0c1ba3c27ebb17c0b496ece778ef11e18 for pr-79470
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fphilipahlberg%2Flookahead" "/workspace/builds/worker-3/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-3/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/philipahlberg/lookahead on toolchain b7ebc6b0c1ba3c27ebb17c0b496ece778ef11e18
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+b7ebc6b0c1ba3c27ebb17c0b496ece778ef11e18" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/philipahlberg/lookahead
[INFO] finished tweaking git repo https://github.com/philipahlberg/lookahead
[INFO] tweaked toml for git repo https://github.com/philipahlberg/lookahead written to /workspace/builds/worker-3/source/Cargo.toml
[INFO] crate git repo https://github.com/philipahlberg/lookahead already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+b7ebc6b0c1ba3c27ebb17c0b496ece778ef11e18" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "rustops/crates-build-env@sha256:c8ac004eab7d63a0ad09a2dde3d3353ba464f767bee4de425dc8f74c46a1905e" "/opt/rustwide/cargo-home/bin/cargo" "+b7ebc6b0c1ba3c27ebb17c0b496ece778ef11e18" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 2f2de251541afe6c53c9ef5b9cd2d2e3b7ccb369112d2204c78502663e56908f
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "2f2de251541afe6c53c9ef5b9cd2d2e3b7ccb369112d2204c78502663e56908f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "2f2de251541afe6c53c9ef5b9cd2d2e3b7ccb369112d2204c78502663e56908f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2f2de251541afe6c53c9ef5b9cd2d2e3b7ccb369112d2204c78502663e56908f", kill_on_drop: false }`
[INFO] [stdout] 2f2de251541afe6c53c9ef5b9cd2d2e3b7ccb369112d2204c78502663e56908f
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "rustops/crates-build-env@sha256:c8ac004eab7d63a0ad09a2dde3d3353ba464f767bee4de425dc8f74c46a1905e" "/opt/rustwide/cargo-home/bin/cargo" "+b7ebc6b0c1ba3c27ebb17c0b496ece778ef11e18" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 21d0ff39e1bea6ee342ffc165ae643e9615fe6251c1256c6934de1be00650bb1
[INFO] running `Command { std: "docker" "start" "-a" "21d0ff39e1bea6ee342ffc165ae643e9615fe6251c1256c6934de1be00650bb1", kill_on_drop: false }`
[INFO] [stderr]     Checking lookahead v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: this method call currently resolves to `<&[T; N] as IntoIterator>::into_iter` (due to autoref coercions), but that might change in the future when `IntoIterator` impls for arrays are added.
[INFO] [stdout]   --> src/lib.rs:63:28
[INFO] [stdout]    |
[INFO] [stdout] 63 |         let inner = [1, 2].into_iter();
[INFO] [stdout]    |                            ^^^^^^^^^ help: use `.iter()` instead of `.into_iter()` to avoid ambiguity: `iter`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(array_into_iter)]` on by default
[INFO] [stdout]    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]    = note: for more information, see issue #66145 <https://github.com/rust-lang/rust/issues/66145>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this method call currently resolves to `<&[T; N] as IntoIterator>::into_iter` (due to autoref coercions), but that might change in the future when `IntoIterator` impls for arrays are added.
[INFO] [stdout]   --> src/lib.rs:70:28
[INFO] [stdout]    |
[INFO] [stdout] 70 |         let inner = [1, 2].into_iter();
[INFO] [stdout]    |                            ^^^^^^^^^ help: use `.iter()` instead of `.into_iter()` to avoid ambiguity: `iter`
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]    = note: for more information, see issue #66145 <https://github.com/rust-lang/rust/issues/66145>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this method call currently resolves to `<&[T; N] as IntoIterator>::into_iter` (due to autoref coercions), but that might change in the future when `IntoIterator` impls for arrays are added.
[INFO] [stdout]   --> src/lib.rs:77:28
[INFO] [stdout]    |
[INFO] [stdout] 77 |         let inner = [1, 2].into_iter();
[INFO] [stdout]    |                            ^^^^^^^^^ help: use `.iter()` instead of `.into_iter()` to avoid ambiguity: `iter`
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]    = note: for more information, see issue #66145 <https://github.com/rust-lang/rust/issues/66145>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this method call currently resolves to `<&[T; N] as IntoIterator>::into_iter` (due to autoref coercions), but that might change in the future when `IntoIterator` impls for arrays are added.
[INFO] [stdout]   --> src/lib.rs:84:28
[INFO] [stdout]    |
[INFO] [stdout] 84 |         let inner = [1, 2].into_iter();
[INFO] [stdout]    |                            ^^^^^^^^^ help: use `.iter()` instead of `.into_iter()` to avoid ambiguity: `iter`
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]    = note: for more information, see issue #66145 <https://github.com/rust-lang/rust/issues/66145>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this method call currently resolves to `<&[T; N] as IntoIterator>::into_iter` (due to autoref coercions), but that might change in the future when `IntoIterator` impls for arrays are added.
[INFO] [stdout]   --> src/lib.rs:92:28
[INFO] [stdout]    |
[INFO] [stdout] 92 |         let inner = [1, 2].into_iter();
[INFO] [stdout]    |                            ^^^^^^^^^ help: use `.iter()` instead of `.into_iter()` to avoid ambiguity: `iter`
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]    = note: for more information, see issue #66145 <https://github.com/rust-lang/rust/issues/66145>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 5 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.53s
[INFO] running `Command { std: "docker" "inspect" "21d0ff39e1bea6ee342ffc165ae643e9615fe6251c1256c6934de1be00650bb1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "21d0ff39e1bea6ee342ffc165ae643e9615fe6251c1256c6934de1be00650bb1", kill_on_drop: false }`
[INFO] [stdout] 21d0ff39e1bea6ee342ffc165ae643e9615fe6251c1256c6934de1be00650bb1